NORTH AMERICAN COLEOPTERA. 77 



As to the tarsi of this genus, some difference of opinion has been ex- 

 pressed, Erichson maintaining a five-jointed tarsus with the first joint 

 small. Duval dissected the tarsus and found four joints only, with the 

 first joint bilobed. On Plate IV will be found a representation of the 

 middle tarsus of our species as it appears to the writer under a power of 

 about fifty diameters ; and I am inclined to agree with Erichson and 

 Lacordaire as to its five-jointed nature, both from analogy and ap- 

 pearance. 



Sub-family III.— CUCUJINAE. 



The chief point of distinction between this sub-family and the preced- 

 ing, is the absence of the corneous plates concealing the maxillae, these 

 being replaced by small projections not separated JVom the other portions 

 of the under surface by a suture. Two tribes are indicated in our fauna 

 as follows: 



First joint of antennae usually moderate ; hind tarsi of 'J, four-jointed. 



I. Cucujisi. 

 First joint of antennae greatly elongated ; tarsi all five-jointed II. Bronti.ni. 



Tribe I.— Cucujini. 

 The table of genera given in the Class, of the Col. of N. A. cited 

 iibove seems to meet most requirements, and I simply transfer it with the 

 following modifications : Narthecius apparently having the greatest affinity 

 with the Passandrinae is placed first, and the striation of tlie prothorax 

 given as the distinguishing feature between it and Ptdlacits instead of 

 the position of the eyes. P((i(indiita is merged with Jjirinophlima, 

 and one new genus is added Thus changed the talkie stands as follows: 



Prosternuni narrow 2. 



Prosternum wide; body depressed 4. 



2. — Hind angles of head prominent 'i. 



Hind angles of head not prominent. 



Body cylindrical: prothorax margined Kartlieoiiis. 



Body depressed ; prothorax not margined I*e(liacii»$. 



3. — Antennae not thicker toward the tip Ouciijiis. 



4. — Elytra very short; prothorax not margineil liio. 



Elytra long; prothorax margined 5. 



Spurs of front tibiae unequal LseiliopliltiPllS. 



Spurs of front tibiae equal I^athropiis. 



5. — Second joint of antennae attached to the side of the first joint wiiicli is of ali- 

 normal form DysiiieriiN. 



In Jjtrniopltlii'na and LuthiopiiA the striae on the prothorax are con- 

 stant in every species and individual which I have examined, and there- 

 fore the ground for the separation of L. (inc/iistii/uK given by l)r. Le- 

 Conte in his Classification will not IkpIiI godd. the posititm of the eyes 

 bc>ing plainly of no value. 



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